The List of Approved Backflow Prevention Assemblies continues to be a valuable source of information for anyone involved in cross-connection control. Keeping up-to-date with the most current List is crucial. The best way to stay current is downloading the List from the USC Foundation’s website since it is updated as changes are made to the List.

The List is comprised of backflow prevention assemblies, which have successfully completed the laboratory and field evaluation phases of the Foundation’s Approval Program. The backflow prevention assemblies are approved for a period of three years and this approval is subject to renewal.

Each approved backflow prevention assembly is listed by the type of assembly, manufacturer’s name, model, size, edition of the manual under which the assembly was approved, approval date, and the latest renewal date. The List also reflects assemblies no longer in production but for which spare parts are still available from the manufacturer.

All of the acceptable shutoff valves, which may be used as replacement shutoff valves, are listed with each approved assembly. The use of shutoff valves other than those listed invalidates the Foundation’s approval. The listing of shutoff valves allows those in the field to replace one or both shutoff valves of a backflow preventer with any of the listed valves.

The USC List is made available digitally in three formats; a sortable Excel format, PDF format and as a web app. The web app is designed for mobile devices and may not display properly on your desktop computer.

The USC List is also made available in printed format but does not include any additions after January 21, 2022. The 2022 USC List Book is a great tool to have when access to the USC List online is not available.

The top of each column in the Excel version of the List can act as filters to filter the exact information needed. One can choose which type of assembly (DC, RP, DCDA, DCDA-II, RPDA-II, RPDA, AVB, PVB, or SVB) at the top of the column. Then only those particular assemblies show on the List. This can be printed and handed out to the customer. With the Excel version of the List, it is much easier to provide the end user with a narrowed down list of what is needed in any specific situation. For example, one could select the following: RP, Lead Free, 2", Vertical up inlet and vertical down outlet. This would generate a list of five acceptable assemblies. and distribute it to their end user.

The USC Foundation's List of Approved Backflow Prevention Assemblies is copyrighted.